change hhd location on ide cable?

[nora.e]

I've got 2 hhd's an 80gb master and a 40gb slave. I'd like to get a fan on the 80. is it posible to swap spots between them by putting the master on the plug marked slave, the slave on the plug marked master, but still have the os recognize the 80 as the master?

[GJSNeptune]

I'm not even sure if the motherboard knows which end of the cable is plugged into what. I'd move them, keep their jumpers the same, and see what happens.